Numbers 25:1

In Shittim. Literally, “acacia trees.” Inasmuch as the word here is in the plural and, in Hebrew, has the definite article with the preposition “in” or “among,” the expression may be translated, “Among the acacia trees.” It is from here that Joshua subsequently sent men to spy out the land of Canaan in the vicinity of Jericho (Joshua 2:1; 3:1). The more complete form of the name is Abel-Shittim (Num. 33:49). Its site, though not definitely known, is in the plains of Moab.

Whoredom. Literal whoredom was followed by its spiritual counterpart — the worship of idols. If the first step had not been taken, the second one would probably not have followed.